AGM versus Calcium

[Raistlin]

My practise is to replace the battery when I buy a car.

My XF is stop / start and has a AGM battery fitted as the main battery.

I've been offered a calcium replacement battery, being told they are "better" than AGM.

Does anybody know the difference please?

[JOE-DOT-COM]

Calcium ones are lead acid batteries, with different grids inside instead of lead,

AGM seen to be the best at the moment, there gel and dont leak and have better output amp and cranking amps

got mine from battery megastore, good value and got it next day, this was before covid though

cheers

Joe

[Raistlin]

Thanks Joe.

[Big John]

Hi

You should always replace an AGM with an AGM. They are a very different design to the standard (including Calcium) wet cell. The main difference is their ability to recover from deep discharge which is what you get with stop/start use. In addition the cars charging system is designed for the difference so if you use the wrong sort you may well get a premature failure of the new battery if it is not an AGM.

https://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

John

 

[PaulT]

and make sure you connect a slave battery to the positive terminal clamp and the earth to a convenient earth point. You can find plenty of posts about central locking not working after disconnecting a battery. Jaguar issued a TSB. Jaguar solution is to replace the Central and Rear Junction Boxes - not cheap, though it seems that they can be reprogrammed via Autologic.

I replaced my batteries a couple of months ago, the stop start was not working, and reset the BMS but no stop start. Then suddenly, the stop start started working last week. A little worrying the first time, thought something had gone wrong when the engine stopped.

[Michael Bunce]

If your car is equipped with "Stop Start" you MUST use an AGM battery.